Rates and Determinants of Mother's Own Milk Feeding in Infants Born Very Preterm

Monitoring the Use of Human Milk, the Ideal Food for Very Low-Birth-Weight Infants-A Narrative Review

Aware of the utmost importance of feeding premature babies-especially those of lower weight-with human milk, as well as the need to monitor this important element of neonatal care, we focused on four aspects in this review. First of all, we reviewed the beneficial effects of feeding premature infants with breast milk in the short and long term. Secondly, we performed a quantitative evaluation of the rates of breastfeeding and feeding with human milk in Very-Low-Birth-Weight infants (VLBWs) during hospitalization in the Neonatal Intensive Care Unit (NICU) and at discharge. Our aim was to take a snapshot of the current status of human milk-feeding care and track its trends over time. Then we analyzed, on the one hand, factors that have been proven to facilitate the use of maternal milk and, on the other hand, the risk factors of not feeding with breast milk. We also considered the spread of human milk banking so as to assess the availability of donated milk for the most vulnerable category of premature babies. Finally, we proposed a protocol designed as a tool for the systematic monitoring of actions that could be planned and implemented in NICUs in order to achieve the goal of feeding even more VLBWs with human milk.

Breastfeeding and human milk in the NICU: From birth to discharge

It is well recognized that human milk is the optimal nutritive source for all infants, including those requiring intensive care. This statement reviews evidence supporting the importance of breastfeeding and human milk for infants, and why breastfeeding practices should be prioritized in the neonatal intensive care unit (NICU). It also reviews how to optimally feed infants based on their stability and maturity, and how to support mothers to establish and maintain milk production when their infants are unable to feed at the breast.

A Quality Improvement Initiative to Reduce Necrotizing Enterocolitis in Very Preterm Infants

OBJECTIVE

To reduce the incidence of necrotizing enterocolitis (NEC) among very preterm infants in the Calgary Health Region to ≤2% within 2 years.

METHODS

A multidisciplinary team developed key drivers for NEC. Targeted interventions included strategies to increase mothers' own milk (MOM), improve compliance with feeding regimens, standardize management of feeding intolerance, prevent intestinal microbial aberrations, and feed conservatively during blood transfusion and the treatment of patent ductus arteriosus. The outcome measure was NEC (≥ stage 2). Changes in NEC rates were examined among racial and ethnic groups. Process measures included MOM feeding at discharge, the difference between actual and expected time to reach full feeds, lowest hemoglobin, and the duration of empirical antibiotics. Growth, the rate of blood transfusion, and the duration of parenteral nutrition were balancing measures. The preintervention, intervention, and sustainment periods were January 2013 to June 2016, July 2016 to December 2018, and December 2018 to December 2021, respectively.

RESULTS

We included 2787 infants born at ≤326/7 weeks' gestation (1105 preintervention, 763 during intervention, and 919 in sustainment). NEC decreased from 5.6% to 1.9%. Process measures indicated increased MOM feeding at discharge, improved compliance with feeding regimens, increased lowest hemoglobin levels, and shorter durations of empirical antibiotics. Balancing measures revealed improved weight Z-scores, shorter durations on parenteral nutrition, and increased rates of blood transfusion.

CONCLUSIONS

Quality improvement initiatives to increase MOM, improve compliance with feeding regimens, feed conservatively during blood transfusion and treatment of patent ductus arteriosus, and prevent intestinal microbial aberrations were associated with reduced NEC.

The Interaction of Early Exclusive Mother's Milk Feeding and Ethnic Background with Ultimate Feeding Outcomes After Very Preterm Birth

Background: Mothers of very preterm infants (born under 32 weeks' gestation) have specific lactation challenges. There is little literature related to the influences on exclusive maternal milk provision. Method: An observational cohort using prospectively entered clinical data in a single tertiary neonatal unit in the United Kingdom over a 2-year period 2019-2021. There were 112 infants born under 32 weeks' gestation who fulfilled inclusion criteria. Results: Average gestation was 27.9 ± 2.6 weeks at birth and 37.3 ± 3.3 at discharge. On day 4 after birth, 29% (31/107) received exclusive maternal milk. At discharge, 54% (60/112) received exclusive maternal milk. Exclusive maternal milk at day 4 was associated with exclusive maternal milk at discharge (adjusted relative risk 2.3, 95% confidence interval 1.5-3.6, p < 0.001). Mothers from "white other," Asian, and mixed/multiple ethnic backgrounds were more likely than white British mothers to give exclusive maternal milk at discharge. This association emerged only after adjustment for exclusive maternal milk at day 4 after birth. Conclusions: The association of minority ethnic background with feeding outcomes that has previously been noted in the United Kingdom general population was also found in this very preterm cohort. The relationship was strengthened after adjustment for exclusive maternal milk at day 4. This may suggest that establishing early milk supply is a universal barrier to later exclusive maternal milk in this population and that once milk supply is established, standard social and cultural experiences come to bear on infant feeding decisions.

Trend and Predictors of Breastmilk Feeding among Very-Low-Birth-Weight Infants in NICU and at Discharge

Mothers' own milk (MOM) for premature babies is considered a life-saving drug for its proven protective action against the complications of prematurity and for effects on outcome in the short and long term, especially neurological ones. We studied the use of MOM for infants weighing <1500 g for a period of 5 years, evaluating the trend over time and the impact of some variables on human milk feeding performance. Statistical comparisons concerned the rate of feeding with breast milk during a stay in an NICU and at discharge with respect to two types of variables: (1) maternal and neonatal characteristics (gestational age, birth weight, type of pregnancy (whether single or twin), maternal age) and (2) feeding characteristics (time of the start of minimal enteral feeding and availability of MOM, days until the achievement of full enteral feeding). Group comparisons were performed using ANOVA or t-test for continuous variables and Pearson chi-squared test or Fisher exact test for categorical variables. We observed an increase, between 2017 and 2021, in MOM use (p = 0.003). The availability of the own mothers' milk occurred, on average, on the fourth day of life and improved over the years. The start of minimal enteral feeding (MEF) with human milk averaged 1.78 days, and 54.3% of VLBWs received MEF with donor milk on the first day of life. The average percentage of feeding with the mothers' milk at discharge was 47.6%, with 36.1% of exclusive MOM and an increase from 45.8% in 2017 (33.3% exclusive) to 58.82% (41.18% exclusive) in 2021. The mean average daily growth of the weight improved (p < 0.001) during this period, and there was no statistical difference between infants fed with maternal milk and those fed with bank milk. Older maternal age, early-start feeding with maternal milk and low gestational age had a statistically significant impact on feeding with MOM at discharge.

Trend over 25 years of risk factors of mother's own milk provision to very low birth weight infants at discharge

BACKGROUND

Feeding mother's own milk (MOM) is associated with reduced morbidity of very low birth weight (VLBW) infants (<1500 g), but not all mothers are able to provide pumped breast milk or breastfeed until discharge.

AIMS

To investigate the duration of MOM feeding and identify risk factors for cessation.

STUDY DESIGN

Single-center retrospective cohort study.

SUBJECTS

307 VLBW infants born 2012 and 2019 surviving beyond 7 days of life.

OUTCOME MEASURES

Analysis of MOM feeding at discharge, including comparison with a historical cohort of infants born 1992-1994.

RESULTS

MOM feeding was initiated in 178/180 infants (98.9 %) born in 2012 and in 123/127 infants (96.9 %) born in 2019 (p = 0.132), as compared to 73/89 (82 %) infants born 1992-1994 (p < 0.001). Median [range] duration of MOM feeding was similar for infants born in 2012 (45 [0-170] days) and 2019 (50 [0-190] days) (p = 0.396), but much longer than in the historical cohort (36 [0-152] days) (p < 0.001). The overall breastfeeding rate increased up to 69.2 % and 77.2 %. Factors associated with cessation of MOM feeding were smoking during pregnancy, single-mother status, short (<12 years) duration of maternal or paternal school education (all p ≤ 0.001), natural conception, birth weight ≥ 1000 g, and gestational age ≥ 29 weeks (p < 0.05). In Cox proportional hazard multivariate analysis, smoking during pregnancy and single-mother status remained independent risk factors.

CONCLUSIONS

Duration of MOM feeding and breastfeeding rates of VLBW infants during hospital stay have increased significantly during the last 30 years, while smoking and indicators of low socioeconomic status remain dominant predictors of cessation of MOM feeding.

Perinatal Factors Associated With Breastfeeding Trends After Preterm Birth <29 Weeks Gestation: Can We Predict Early Discontinuation?

OBJECTIVE

To determine the rates and perinatal factors associated with initiation and early discontinuation of breastfeeding among very preterm neonates.

METHODS

This was a retrospective cohort study of very preterm infants (<29 weeks gestation) admitted to 2 regional Level III neonatal intensive care units (NICUs) from January 1, 2015, to December 31, 2019. A national neonatal database was used to evaluate initiation and continuation rates of breastfeeding and associated perinatal factors. Stored nutrition profiles and delivery record books were used to determine feeding volumes associated with continuation of breastfeeding to hospital discharge for a subgroup of infants at a single site. Descriptive and inferential statistics were used to present the results between groups, and logistic regression modeling was used to calculate crude and adjusted odds ratios (OR) and 95% CI.

RESULTS

Of 391 eligible neonates, 84% initiated breastfeeding but only 38% continued to discharge. Interestingly, frequency of breastfeeding initiation (P < 0.001) and continuation (P < 0.001) declined over the study period. After adjustment for confounders, younger maternal age, earlier gestational age, cigarette smoking, and multiparity were significantly associated with early discontinuation of breastfeeding prior to hospital discharge. Early discontinuation of breastfeeding was also related to lower volumes of breastmilk by day 7 of life (P = 0.004).

CONCLUSION

Very preterm neonates are at high risk for non-initiation and early discontinuation of breastfeeding. The early postnatal period represents a critical time to establish breastmilk volumes, and the identification of key perinatal risk factors allows for early and targeted breastfeeding support.

Associations of Maternal Milk Feeding With Neurodevelopmental Outcomes at 7 Years of Age in Former Preterm Infants

IMPORTANCE

Maternal milk feeding may have unique long-term neurodevelopmental benefits in very preterm infants.

OBJECTIVE

To examine the extent to which maternal milk feeding after very preterm birth is associated with cognitive, academic, and behavioral outcomes at school age.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study assessed 586 infants born at less than 33 weeks' gestation at 5 Australian perinatal centers and enrolled in the Docosahexaenoic Acid for Improvement of Neurodevelopmental Outcomes study (January 1, 2001, to December 31, 2005) who were evaluated at a corrected age of 7 years. The statistical analysis was completed on January 19, 2022.

EXPOSURES

Maternal milk intake, including mean volume (milliliters per kilogram per day) during neonatal hospitalization and total duration (in months).

MAIN OUTCOMES AND MEASURES

Neurodevelopmental outcomes at 7 years of age were (1) IQ (Wechsler Abbreviated Scale of Intelligence), (2) academic achievement (Wide Range Achievement Test, Fourth Edition), (3) symptoms of attention-deficit/hyperactivity disorder (ADHD) (Conners Third Edition ADHD Index, parent reported), (4) executive function (Behavior Rating Inventory of Executive Functioning, parent reported), and (5) behavior (Strengths and Difficulties Questionnaire, parent reported).

RESULTS

A total of 586 infants (mean [SD] gestational age at birth, 29.6 [2.3] weeks; 314 male [53.6%]) born to 486 mothers (mean [SD] age, 30.6 [5.5] years; 447 [92.0%] White) were included. Mean (SD) maternal milk intake in the neonatal intensive care unit was 99 (48) mL/kg daily, and mean (SD) maternal milk duration was 5.1 (5.4) months. Mean (SD) full-scale IQ was 98.5 (13.3) points. After covariate adjustment, higher maternal milk intake during the neonatal hospitalization was associated with higher performance IQ (0.67 points per additional 25 mL/kg daily; 95% CI, 0.10-1.23 points), reading scores (1.14 points per 25 mL/kg daily; 95% CI, 0.39-1.89 points), and math scores (0.76 points per 25 mL/kg daily; 95% CI, 0.14-1.37 points) and fewer ADHD symptoms (-1.08 points per 25 mL/kg daily; 95% CI, -1.96 to -0.20 points). Longer duration of maternal milk intake was associated with higher reading (0.33 points per additional month; 95% CI, 0.03-0.63 points), spelling (0.31 points per month; 95% CI, 0.01-0.62 points), and math (0.30 points per month; 95% CI, 0.03-0.58 points) scores. Maternal milk was not associated with improved full-scale IQ, verbal IQ, executive function, or behavior. Most associations were stronger among infants born at lower gestational ages, particularly less than 30 weeks (interaction P values <.01).

CONCLUSIONS AND RELEVANCE

In this cohort study of preterm infants, maternal milk feeding during the neonatal hospitalization and after discharge were associated with better school-age performance IQ and academic achievement and with a reduction in ADHD symptoms, particularly among infants born at less than 30 weeks' gestation.

25 Years of Research in Human Lactation: From Discovery to Translation

Researchers have recently called for human lactation research to be conceptualized as a biological framework where maternal and infant factors impacting human milk, in terms of composition, volume and energy content are studied along with relationships to infant growth, development and health. This approach allows for the development of evidence-based interventions that are more likely to support breastfeeding and lactation in pursuit of global breastfeeding goals. Here we summarize the seminal findings of our research programme using a biological systems approach traversing breast anatomy, milk secretion, physiology of milk removal with respect to breastfeeding and expression, milk composition and infant intake, and infant gastric emptying, culminating in the exploration of relationships with infant growth, development of body composition, and health. This approach has allowed the translation of the findings with respect to education, and clinical practice. It also sets a foundation for improved study design for future investigations in human lactation.